Hi Adventure950,

That sounds spot on...cost is usually the giveaway.

So, what you are experiencing is the reduction in the effect of the DWR finish. You are correct that road salts/oil/grime all have a negative effect on the original DWR finish, and that cleaning and re-treating with aftermarket products only goes so far. Part of the problem there is that the original DWR finishes are heat-set at a very high temp...as high as the nylon will allow without breaking down. There is no way to re-produce that at home, even in the hottest of dryers.

Here is another problem with maintaining these finishes: in order to clean them, you need to use a detergent (especially for road oils/grime). Getting the detergent completely back out of the fabric is nearly impossible. Detergent kills the DWR effect dramatically. It is in fact an "anti-DWR", and a very powerful one at that. So you are fighting this battle at home as well. Multiple rinsings (preferably in a tub where there is no chance for residual detergent to be present) are the best way to beat this.

Nobody, including us, has been able to solve these issues with a permanent finish. It is a sort of "Holy Grail" of fabric finishing technology. The best you can get is high durability + oil resistance. Very few DWRs out there have an oil-resistant component. (our nanosphere is one). The oil resist helps, but still does not eliminate the problem!